Display device

ABSTRACT

A display device includes a substrate, conductive pads arranged on the substrate over a plurality of rows, and a drive circuit chip including bumps arranged over a plurality of rows to be electrically connected with the conductive pads, and the conductive pads arranged in a same row are arranged in parallel, and the bumps arranged in a same row are arranged in a zigzag form so as to be partially shifted.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.15/807,455, filed on Nov. 8, 2017, which claims priority to and thebenefit of Korean Patent Application No. 10-2016-0161408, filed on Nov.30, 2016 in the Korean Intellectual Property Office, the entiredisclosure of each of which is incorporated herein by reference.

BACKGROUND 1. Field

Aspects of embodiments of the present invention relate to a displaydevice.

2. Description of the Related Art

Various kinds of display devices, such as an electrowetting displaydevice (EWD), an electrophoresis display device (EPD), a plasma displaypanel (PDP), a field emission display device (FED), a liquid crystaldisplay device (LCD), and an organic light emitting diode display device(OLED), have been developed.

Such a display device includes a display area in which a plurality ofpixels is arranged to display an image and a non-display area in whichdrive integrated circuits for driving pixels (herein, referred to as“drive circuit chip”) are disposed.

The drive circuit chip disposed in the non-display area is generallyfabricated in the form of a chip, and is mounted according to a chip onglass (COG) method or is mounted on a display panel according to a tapecarrier package (TCP) method using a tape automated bonding (TAB)technology.

Recently, compact display devices have been required. Thus, a displaydevice in which a drive circuit chip is directly mounted on the edge ofa substrate to improve integration degree has been developed and used.Further, a flexible display device formed using a plastic substrate hasbeen developed.

However, there are many technical difficulties in directly mounting adrive circuit chip on a substrate. When the drive circuit chip isdirectly mounted on the substrate, there is a problem that the pads andwirings of the substrate electrically connected with the drive circuitchip are cracked or broken due to factors such as pressure andtemperature during the mounting process. In particular, such defects aremore serious in the case of a flexible display device.

SUMMARY

According to an exemplary embodiment of the present disclosure, adisplay device includes a substrate, conductive pads arranged on thesubstrate over a plurality of rows, and a drive circuit chip includingbumps arranged over a plurality of rows to be electrically connectedwith the conductive pads, wherein conductive pads arranged in a same roware arranged in parallel, and the bumps arranged in a same row arearranged in a zigzag form so as to be partially shifted.

According to another exemplary embodiment of the present disclosure, adisplay device includes a substrate, conductive pads arranged on thesubstrate over a plurality of rows, and a drive circuit chip includingbumps arranged over a plurality of rows to be electrically connectedwith the conductive pads, wherein a shifted length between theconductive pads arranged adjacent to a same row in a column directionperpendicular to a row direction is shorter than a shifted lengthbetween the bumps arranged adjacent to a same row in the columndirection.

According to an aspect of the present invention, a display deviceincludes a drive circuit chip safely mounted on a substrate withoutcausing cracks or damage.

However, aspects of the present invention are not restricted to theabove aspects. The above and other aspects of the present invention willbecome more apparent to one of ordinary skill in the art to which thepresent invention pertains by referencing the detailed description ofsome embodiments of the present invention set forth below.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other aspects and features of the present invention willbecome more apparent by describing in further detail some exemplaryembodiments thereof with reference to the attached drawings, in which:

FIG. 1 is a perspective view of a display device according to anembodiment of the present invention;

FIG. 2 is a layout diagram of a region “A” of FIG. 1, showing bumps andpads of the display device of FIG. 1;

FIG. 3 is an enlarged layout diagram of a region “B” of FIG. 2;

FIG. 4 is a sectional view taken along the line I-I′ of FIG. 3;

FIG. 5 is a sectional view taken along the line II-II′ of FIG. 1;

FIG. 6 is an enlarged layout diagram of the region “B” of FIG. 2,showing output bumps arranged in the region “B”;

FIG. 7 is a graph showing measured values of pressures applied to firstto fifth points shown in FIG. 2 in some experimental examples;

FIG. 8 is a graph showing measured values of pressures applied to thefirst to fifth points shown in FIG. 2 in some other experimentalexamples;

FIG. 9 is a sectional view of a base substrate of the display device ofFIGS. 4 and 5, where the base substrate is a flexible substrate,according to an embodiment of the present invention;

FIG. 10 is an enlarged layout diagram of a region corresponding to theregion “B” of FIG. 2 of a display device according to a modifiedembodiment of the present invention;

FIG. 11 is an enlarged layout diagram showing output bumps arranged inthe region shown in FIG. 10;

FIG. 12 is an enlarged layout diagram of a region corresponding to theregion “B” of FIG. 2 of a display device according to another modifiedembodiment of the present invention;

FIG. 13 is an enlarged layout diagram showing output bumps arranged inthe region shown in FIG. 12;

FIG. 14 is an enlarged layout diagram of a region corresponding to theregion “B” of FIG. 2 of a display device according to another modifiedembodiment of the present invention;

FIG. 15 is an enlarged layout diagram showing output bumps arranged inthe region shown in FIG. 14;

FIG. 16 is an enlarged layout diagram of a region corresponding to theregion “B” of FIG. 2 of a display device according to another modifiedembodiment of the present invention;

FIGS. 17 to 21 are enlarged layout diagrams respectively showing outputbumps of display devices arranged in regions corresponding to the region“B” of FIG. 2, according to other modified embodiments of the presentinvention;

FIG. 22 is a layout view showing bumps and pads of a display devicearranged in a region corresponding to the region “A” of FIG. 1,according to another modified embodiment of the present invention; and

FIG. 23 is a layout view showing bumps and pads of a display devicearranged in a region corresponding to the region “A” of FIG. 1,according to another modified embodiment of the present invention.

DETAILED DESCRIPTION

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, in which some exemplaryembodiments of the invention are shown. This invention may, however, beembodied in different forms and should not be construed as limited tothe embodiments set forth herein. Rather, these embodiments are providedso that this disclosure will be thorough and complete, and will conveythe scope of the invention to those skilled in the art. The samereference numbers indicate the same components throughout thespecification. In the attached drawing figures, the thickness of layersand regions may be exaggerated for clarity.

It is to be understood that, although the terms “first,” “second,”“third,” etc., may be used herein to describe various elements, theseelements should not be limited by these terms. These terms are only usedto distinguish one element from another element. Thus, a first elementdiscussed below could be termed a second element without departing fromthe teachings of the invention.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms, including “at least one,” unless the content clearly indicatesotherwise. As used herein, “or” means “and/or,” and the term “and/or”includes any and all combinations of one or more of the associatedlisted items. It will be further understood that the terms “comprises”and/or “comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

Spatially relative terms, such as “beneath,” “below,” “lower,” “above,”“upper,” and the like, may be used herein for ease of description todescribe one element or feature's relationship to another element(s) orfeature(s) as illustrated in the figures. It will be understood that thespatially relative terms are intended to encompass differentorientations of the device in use or operation in addition to theorientation depicted in the figures. For example, if the device in thefigures is turned over, elements described as “below” or “beneath” otherelements or features would then be oriented “above” the other elementsor features. Thus, the exemplary term “below” can encompass both anorientation of above and below. The device may be otherwise oriented(e.g., rotated 90 degrees or at other orientations) and the spatiallyrelative descriptors used herein interpreted accordingly.

In the present invention, an electronic apparatus may be any apparatusprovided with a display device. Examples of the electronic apparatus mayinclude smart phones, mobile phones, navigators, game machines, TVs, carhead units, notebook computers, laptop computers, tablet computers,personal media players (PMPs), and personal digital assistants (PDAs).The electronic apparatus may be embodied as a pocket-sized portablecommunication terminal having a wireless communication function.Further, the display device may be a flexible display device capable ofchanging its shape.

Hereinafter, some embodiments of the present invention will be describedwith reference to the attached drawings.

FIG. 1 is a perspective view of a display device according to anembodiment of the present invention.

Referring to FIG. 1, a display device according to an embodiment of thepresent invention includes a first substrate 100, a second substrate200, a drive circuit chip 300, and a flexible circuit board 400. Here,the second substrate 200 has a smaller area than the first substrate100.

An area where the first substrate 100 and the second substrate 200overlap each other is referred to as a display area DA, and an edge areaof the first substrate 100 not overlapping the second substrate 200 isreferred to as a non-display area NDA.

A plurality of pixels PX is arranged in the display area DA, and thedrive circuit chip 300 for driving the pixels PX is mounted in thenon-display area NDA. That is, the drive circuit chip 300 may be mountedon the first substrate 100 in the non-display area NDA.

The drive circuit chip 300 applies drive signals to the plurality ofpixels PX arranged in the display area DA, and thus a desired image maybe displayed on the plurality of pixels PX arranged in the display areaDA. The plurality of pixels PX may be arranged in the form of a matrixalong a first directional axis D1 and a second directional axis D2 whichare orthogonal to each other. The drive circuit chip 300 may include adrive circuit body 310 and a plurality of conductive bumps (not shown)including an output bump OPB.

In an embodiment of the present invention, the pixels PX may includefirst to third pixels (not shown) respectively expressing a red color, agreen color, and a blue color. In some embodiments of the presentinvention, the pixels PX may further include some of pixels respectivelyexpressing yellow, cyan, and magenta. Moreover, the present invention isnot limited thereto, and the pixels PX may further include a pixelexpressing white.

Depending on the structure of the pixels PX, display devices may beclassified into any of a liquid crystal display device, an organic lightemitting display device, and the like. As the display device accordingto an embodiment, an organic light emitting display device will bedescribed as an example. However, the present invent invention is notlimited thereto, and it is to be understood that the content accordingto each embodiment of the present invention may be applied to a liquidcrystal display device or the like.

The drive circuit chip 300 and the first substrate 100 are electricallyconnected to each other through a plurality of conductive pads (notshown) formed in the drive circuit chip 300 and a plurality ofconductive pads (not shown) formed on the first substrate 100. Theplurality of conductive pads formed on the first substrate 100 may beconnected to the respective pixels PX through a plurality of conductivelines, so as to transmit the signals inputted from the drive circuitchip 300 to the pixels PX.

The flexible circuit board 400 may include a plurality of conductivelines (not shown), and may be disposed in the non-display area NDA. Theflexible circuit board 400 may provide externally provided signals suchas a video data signal (not shown), a vertical synchronization signal(not shown), and the like to the first substrate 100, and may transmitthese signals to the drive circuit chip 300.

Referring to FIG. 2, a relationship between the drive circuit chip 300and the first substrate 100 will be further described.

FIG. 2 is a layout diagram of a region “A” showing bumps and pads of thedisplay device of FIG. 1.

Referring to FIG. 2, the first substrate 100 of the display deviceaccording to an embodiment of the present invention includes an inputpad region IPDR, a side pad region SPDR, and an output pad region OPDR.

The input pad region IPDR may include a plurality of input pads IPDsarranged along the first directional axis D1 to form a row. Therespective input pads IPDs may be arranged to correspond to input bumpsIPBs. The side pad region SPDR may include a plurality of side pads SPDsarranged along the second directional axis D2 to form a column. Therespective side pads SPDs may be arranged to correspond to side bumpsSPBs.

The illustrated arrangement of the input pads IPDs and the side padsSPDs respectively included in the input pad region IPDR and the side padregion SPDR is exemplary. That is, the arrangement of the input padsIPDs and the side pads SPDs may be changed in accordance with anarrangement of the input bumps IPBs of the drive circuit chip 300connected to the respective input pads IPDs and the side bumps SPBs ofthe drive circuit chip 300 connected to the respective side pads SPDs.

The input pad region IPDR and the side pad region SPDR are provided withvarious signals provided from the outside of the display deviceaccording to an embodiment of the present invention, and the varioussignals may be provided to the drive circuit chip 300 through theplurality of input bumps IPBs arranged corresponding to the input padregion IPDR and the plurality of side bumps SPBs arranged correspondingto the side pad region SPDR.

The output pad region OPDR includes a plurality of output pads OPDs. Theoutput pad region OPDR may include a plurality of output pad rows OPD_Rsin each of which a plurality of output pads OPDs are arranged along thefirst directional axis D1. As shown in FIG. 2, the output pad regionOPDR may include first to fourth output pad rows OPD_R1, OPD_R2, OPD_R3,and OPD_R4, for example.

The output pad region OPDR can receive various signals outputted fromthe drive circuit chip 300 through a plurality of output bumps OPBsarranged corresponding to the output pad region OPDR. The varioussignals provided to the output pad region OPDR may be provided to eachof the pixels PX arranged in the display area DA through a plurality oflines (not shown) connected to the output pad region OPDR. Here, sincethe number of pixels PX controlled by the drive circuit chip 300 is verylarge, the output pad region OPDR may include a number of output padsOPDs greater than the number of the input pads IPDs of the input padregion IPDR or the number of the side pads SPDs of the side pad regionSPDR.

In an embodiment, the output pads OPDs included in each of the first tofourth output pad rows OPD_R1, OPD_R2, OPD_R3, and OPD_R4 may have thesame shape as each other, and may be arranged parallel to each other.That is, the respective output pads OPDs arranged in the same row may bearranged in parallel so as to be in contact with one reference lineextending along the row direction. In the embodiment shown in FIG. 2,the row direction may be the same as a direction in which the firstdirection axis D1 extends.

Referring to FIG. 3, in an embodiment, each of the output pads OPDsarranged in the same row may be disposed such that one end of the columndirection (that is, a direction in which the second directional axis D2extends) is in contact with a first reference line STL1 extending alongthe row direction (that is, a direction in which the first directionalaxis D1 extends). Also, each of the output pads OPDs arranged in thesame row may be disposed such that the other end (i.e. an end oppositeto the one end) of the column direction (that is, a direction in whichthe second directional axis D2 extends) is in contact with a secondreference line STL2 extending along the row direction (that is, adirection in which the first directional axis D1 extends) in parallel tothe first reference line STL1.

In contrast, with further reference to FIG. 6, the respective outputbumps OPBs arranged to correspond to the output pad region OPDR, thatis, the respective output bumps OPBs connected to the respective outputpads OPDs included in the output pad region OPDR may be arranged to havea specific pattern. That is, the output bumps OPBs may include outputbump rows OPB_R1, OPB_R2, OPB_R3, and OPB_R4 in each of which aplurality of output bumps OPBS are arranged along the first directionalaxis D1.

However, the output bumps OPBs included in the output bump rows OPB_R1,OPB_R2, OPB_R3, and OPB_R4 may have the same shape as each other, butmay not be arranged in parallel to each other. In an embodiment, theoutput bumps OPBs arranged in the same row may be arranged to be shiftedfrom each other in a zigzag form. That is, the output bumps OPBsarranged in the same row and adjacent to each other may be arranged tobe partially shifted in the column direction (that is, a direction inwhich the second directional axis D2 extends).

In an embodiment, the output pads OPDs are not limited to being arrangedin parallel along the row direction (that is, a direction in which thefirst direction axis D1 extends), and may also be arranged to be shiftedin the column direction (that is, a direction in which the seconddirectional axis D2 extends) between the output pads OPDs disposedadjacent to the same row. However, this case may be limited to a casewhere the lengths shifted in the column direction (that is, a directionin which the second directional axis D2 extends) between the output padsOPDs disposed adjacent to the same row are smaller than the lengths ofthe output bumps OPBs arranged corresponding to each other and arrangedadjacent to the same row shifted in the column direction (that is, adirection in which the second directional axis D2 extends).

From the aforementioned arrangement of the output pads OPDs and theoutput bumps OPBs, cracks and damage which may occur in mounting thedrive circuit chip 300 can be minimized or reduced. A more detaileddescription of the arrangement of the output pads OPD and the outputbumps OPBs will be described later. Referring to FIGS. 3 to 5, thestructure of the output pads OPDs and the lines (not shown) connected tothe output pads OPDs will be further described.

FIG. 3 is an enlarged layout diagram of a region “B” of FIG. 2; and FIG.4 is a sectional view taken along the line I-I′ of FIG. 3. Further, FIG.5 is a sectional view taken along the line II-II′ of FIG. 1.

In FIGS. 3 and 4, only the non-display area NDA of the first substrate100 and the drive circuit chip 300 mounted thereon are shown. However,in order to clarify the relationship between each of the componentsarranged in the non-display area NDA of the first substrate 100 and eachof the components arranged in the display area DA of the first substrate100, FIG. 5, which is a sectional view of one pixel PX disposed in thedisplay area DA, is additionally referred to.

Referring to FIGS. 3 to 5, the display device according to an embodimentof the present invention includes the first substrate 100 and the secondsubstrate 200.

In an embodiment, the first substrate 100 includes a base substrate 110,a buffer layer 120, a semiconductor layer 131, a first insulating layer135, a pad line OPL, a gate electrode 141, a second insulating layer145, an output pad OPD, a source electrode 151, a drain electrode 152, apassivation layer 155, and an organic light emitting element 166.

In an embodiment, the base substrate 110 is made of a polymer materialhaving excellent heat resistance, such as polyimide (PI), polyamide(PA), polyethylene terephthalate (PET), fiber-reinforced polymers (FRP),polycarbonate, polyethersulfone, polyarylate (PAR), and polyethylenenaphthalate (PEN). However, the material of the base substrate 110 isnot limited to the aforementioned polymer materials, and may be anymaterial capable of performing a thin film process on the base substrate110 and having excellent heat resistance.

The buffer layer 120 is disposed on one surface of the base substrate110. The buffer layer 120 prevents or substantially prevents impuritiespresent in the base substrate 110 from being introduced into the pixelPX during a manufacturing process. In particular, the buffer layer 120may prevent or substantially prevent the impurities from diffusing intothe semiconductor layer 131 of the pixel PX. The impurities may beintroduced from the outside, or may be generated by the thermaldecomposition of the base substrate 110. The impurities may be gas orsodium discharged from the base substrate 110. In addition, the bufferlayer 120 may block moisture flowing into the pixel PX from the outside.

The semiconductor layer 131 is disposed on one surface of the bufferlayer 120. The semiconductor layer 131 may contain polysilicon oramorphous silicon formed at a low temperature. In addition, thesemiconductor layer 131 may contain a metal oxide semiconductor. Thesemiconductor layer 131 includes a channel region serving as a passagethrough which electrons or holes can travel, and a first ion dopingregion (not shown) and a second ion doping region (not shown) betweenwhich the channel region is disposed. The semiconductor layer 131 canfunction as a channel of a plurality of transistors arranged in eachpixel PX.

The first insulating layer 135 is disposed on the semiconductor layer131 to cover the semiconductor layer 131. The first insulating layer 135includes an organic film and/or an inorganic film. In an embodiment, thefirst insulating layer 135 may include a plurality of inorganic thinfilms. The plurality of inorganic thin films may include a siliconnitride layer and a silicon oxide layer.

The gate electrode 141 and the pad line OPL are disposed on one surfaceof the first insulating layer 135. In an embodiment, the gate electrode141 and the pad line OPL are made of a metal, such as Al, Ag, Cr, Ti,Ta, or Mo, or an alloy thereof. Although the gate electrode 141 and thepad line OPL are shown as a single layer in the drawings according tothe present embodiment, the gate electrode 141 and the pad line OPL maybe formed of a multilayer including a metal layer of Cr, Mo, Ti, Ta, oran alloy thereof, which is excellent in physiochemical properties, and ametal layer of an Al-based metal or an Ag-based metal. In addition, thegate electrode 141 and the pad line OPL may be formed of various metalsor conductors, and, in an embodiment, the gate electrode 141 and the padline OPL are multilayer films that can be patterned under the sameetching conditions.

Although not shown, a plurality of gate lines (not shown) disposed tocross the plurality of pixels PX may be disposed in the display area DA.

The second insulating layer 145 is disposed on one surface of the gateelectrode 141 and the pad line OPL. The second insulating layer 145includes an organic film and/or an inorganic film. The second insulatinglayer 145 may include a plurality of inorganic thin films. The pluralityof inorganic thin films may include a silicon nitride layer and asilicon oxide layer. In an embodiment, the second insulating layer 145may be made of silicon nitride (SiNx) or the like.

The output pad OPD, the source electrode 151, and the drain electrode152 are disposed on one surface of the second insulating layer 145. Morespecifically, the output pad OPD is disposed in the non-display areaNDA, and the source electrode 151 and the drain electrode 152 aredisposed in the display area DA.

The output pad OPD, the source electrode 151, and the drain electrode152, similarly to the gate electrode 141 and the pad line OPL, may bemade of a conductive material, such as chromium, molybdenum, aluminum oran alloy thereof, and may be formed as a single layer or a multilayer.

The output pad OPD may be connected to an output line through a firstcontact hole CH1 penetrating the second insulating layer 145. The signalprovided to the output pad OPD may be provided to the pixel PX disposedin the display area DA through the output line.

At least a part of the source electrode 151 overlaps the gate electrode141, and at least a part of the drain electrode 152 overlaps the gateelectrode 141.

The source electrode 151 may be connected to the semiconductor layer 131through a second contact hole CH2 penetrating the second insulatinglayer 145. The drain electrode 152 may be connected to the semiconductorlayer 131 through a third contact hole CH 3 penetrating the secondinsulating layer 145. The source electrode 151, the drain electrode 152,and the semiconductor layer 131 may constitute a thin film transistor TRfor controlling the driving of the pixel PX. In another embodiment ofthe present invention, the thin film transistor TR may be modified intoa bottom gate structure and then implemented.

Since the display area DA and the non-display area NDA are differentfrom each other in the lamination structure on one side of the outputpad OPD, the source electrode 151, and the drain electrode 152, thelamination structure of the non-display area NDA will be described afterthe description of the lamination structure of the display area DA.

The passivation layer 155 is disposed on the source electrode 151 andthe drain electrode 152 in the display area DA. The passivation layer155 is disposed to overlap the second insulating layer 145, the outputpad OPD, the source electrode 151, and the drain electrode 152, whichare exposed upwards, and includes an organic film and/or an inorganicfilm. In an embodiment, the passivation layer 155 may contain an organicmaterial to provide a planar surface.

A pixel defining layer 167 and the organic light emitting element 166are disposed on one surface of the passivation layer 155. The organiclight emitting element 166 includes an anode electrode 161, a holetransporting region 162, a light emitting layer 163, an electrontransporting region 164, and a cathode electrode 165. The anodeelectrode 161 is connected to the drain electrode 152 through a fourthcontact hole CH4 penetrating the passivation layer 155. In anembodiment, the positions of the anode electrode 161 and the cathodeelectrode 165 of the organic light emitting element 166 may be mutuallychanged.

The anode electrode 161 is disposed on one surface of the passivationlayer 155. The opening OP of the pixel defining layer 167 exposes theanode electrode 161.

The anode electrode 161 may be a pixel (PX) electrode or a positiveelectrode. The anode electrode 161 may be a multi-layer structure havinga plurality of layers made of a transparent metal oxide and a metal. Forexample, the anode electrode 161 may be made of ITO (indium tin oxide),IZO (indium zinc oxide), ZnO (zinc oxide), ITZO (indium tin zinc oxide),or the like. However, in another embodiment in which the anode electrode161 is a semi-transmissive electrode or a reflective electrode, theanode electrode 161 may contain Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, or amixture thereof.

The hole transporting region 162 is disposed on the anode electrode 161.The hole transporting region 162 may include at least one of a holeinjection layer (not shown), a hole transporting layer (not shown), abuffer layer (not shown), and an electron blocking layer (not shown).

The light emitting layer 163 is disposed on the hole transporting region162. The light emitting layer 163 is not particularly limited as long asit is made of a commonly used material. For example, the light emittinglayer 163 may be made of a material that emits red light, green light,and/or blue light, and may contain a fluorescent material or aphosphorescent material. Further, the light emitting layer 163 mayinclude a host and a dopant.

The electron transporting region 164 is disposed on the light emittinglayer 163. The electron transporting region 164 may include at least oneof a hole blocking layer (not shown), an electron transporting layer(not shown), and an electron injection layer (not shown).

The cathode electrode 165 is disposed on the electron transportingregion 164.

The cathode electrode 165 may be a common electrode or a negativeelectrode. The cathode electrode 165 may be a transmissive electrode, asemi-transmissive electrode, or a reflective electrode. In the case inwhich the cathode electrode 165 is a transmissive electrode, the cathodeelectrode 165 may be made of ITO (indium tin oxide), IZO (indium zincoxide), ZnO (zinc oxide), ITZO (indium tin zinc oxide), or the like. Inthe case in which the cathode electrode 165 is a semi-transmissiveelectrode or a reflective electrode, the cathode electrode 165 maycontain Ag, Mg, Al, Pt, Pd, Au, Ni, Nd, Ir, Cr, Li, Ca, LiF/Ca, LiF/Al,Mo, Ti, or a compound or mixture thereof (for example, a mixture of Agand Mg).

The second substrate 200 is disposed on the cathode electrode 165. Thesecond substrate 200 can protect the organic light emitting element 166in the display device from the outside, and may be formed of anencapsulation layer. The encapsulation layer may include a single filmor a plurality of thin film encapsulation layers. In an embodiment, thethin film encapsulation layers may include an inorganic film made ofsilicon nitride and silicon oxide and an organic film made of monomers,and may also be formed of an organic hybrid.

Herein, the lamination structure of the non-display area NDA will bedescribed.

An anisotropic conductive film (ACF) 500 is disposed on the output padOPD disposed in the non-display area NDA. The anisotropic conductivefilm 500 includes a plurality of conductive balls 510 having thecharacteristics of transmitting electricity and a film layer 520 formaintaining a film shape. The anisotropic conductive film 500 mayelectrically connect the input bump IPB, the side bump SPB and theoutput bump OPB of the drive circuit chip 300 to each other, and mayelectrically connect the input pad IPD, the side pad SPD and the outputpad OPD of the first substrate 100 to each other. The anisotropicconductive film 500 may allow the drive circuit chip 300 to be mountedon the first substrate 100.

A method of connecting the drive circuit chip 300 with the firstsubstrate 100 using the anisotropic conductive film 500 according to anembodiment will be described. First, the anisotropic conductive film 500is formed on the output pads OPDs, and the drive circuit chip 300 isdisposed on the anisotropic conductive film 500. Then, heat and pressureare applied to allow the output pads OPDs and the output bumps OPBs ofthe drive circuit chip 300 to be close to each other. Thus, upperportions of the conductive balls 510 may be in contact with the outputbumps OPBs, and lower portions of the conductive balls 510 may be incontact with the output pads OPDs. As a result, the output pads OPDs andthe output bumps OPBs may be electrically connected through theconductive balls 510.

Although there may be a problem of the output pad OPD, and additionallyother components of the first substrate 100, being cracked or damaged bythe aforementioned process of applying heat and pressure to theanisotropic conductive film 500, the cracks and damage may be minimizedor reduced due to the aforementioned zigzag arrangement of the outputpumps OPBs. The reason for this is that, when the output bumps OPBs arearranged in a zigzag form, the pressure applied to the first substrate100 is reduced, compared to when the output bumps OPBs are arrangedparallel to each other.

However, there may be a numerical limitation in the degree to which theoutput bumps OPB are shifted in a zigzag form. Normally, the remainingconductive balls 510 other than the conductive balls 510 electricallyconnecting the output bumps OPBs and the output pads OPDs may be pushedto a region other than the region where the output pads OPD and theoutput bumps OPBs are arranged, as heat and pressure are applied to theanisotropic conductive film 500. However, when the shifted degree of theoutput bumps OPB in the zigzag form is excessive, the output bumps OPBsmay block the path through which the conductive balls 510 are pushed,and thus the conductive balls 510 may be arranged so as to beexcessively aggregated in a specific region. In this case, there may bea possibility of the output bumps OPBs or the output pads OPDs beingelectrically connected to a configuration in which electrical connectionis not intended, and defects may occur. That is, defects due to theconductive balls 510 included in the anisotropic conductive film 500 canbe minimized or reduced by avoiding the excessive zigzag arrangements ofthe output bumps OPBs while appropriately adjusting the pressure appliedto the first substrate 100 by the output bumps OPBs due to the zigzagarrangement of the output bumps OPB. A specific numerical range of thezigzag arrangement of the output bumps (OPB), satisfying this condition,will be described later.

The drive circuit chip 300 including the output bumps OPBs is disposedon the anisotropic conductive film 500. As described above, since thedrive circuit chip 300 is directly mounted on the first substrate 100,the display device can be manufactured flexibly and further integrated.However, the present invention is not limited to the arrangement of theanisotropic conductive film 500, and an isotropic conductive film (notshown) may also be disposed.

Herein, the arrangement structure of the output bumps OPB will bedescribed in more detail.

FIG. 6 is an enlarged layout diagram of the region “B” of FIG. 2,showing output bumps arranged.

Referring to FIG. 6, as described above, the first to fourth output bumprows OPB_R1, OPB_R2, OPB_R3, and OPB_R4 are disposed in the non-displayarea NDA of the first substrate 100. The respective output bumps OPBarranged in the same row may be arranged in a zigzag form to be shiftedfrom each other. That is, among the respective output bumps OPBsarranged in the same row, odd-numbered output bumps OPBs are arranged inparallel to each other along the row direction (that is, a direction inwhich the first direction axis D1 extends), and even-numbered outputbumps OPBs are arranged in parallel to each other along the rowdirection (that is, a direction in which the first direction axis D1extends), but the odd-numbered output bumps OPBs and the even-numberedoutput bumps OPBs may not be arranged in parallel along the rowdirection (that is, a direction in which the first direction axis D1extends).

In an embodiment, for a more detailed description of the stable mountingeffect of the drive circuit chip 300 according to the detailed numericalvalues of the arrangement of the output bumps OPB, some numerical valueswill be defined regarding the arrangement of the output bumps OPBincluded in the first output bump row OPB_R1 of FIG. 6.

First, when an output bump OPB of two adjacent output bumps OPB disposedin the first output bump row OPB_R1 is arranged to be shifted to theupper end (that is, in a direction opposite to the direction in whichthe second direction axis D2 extends) in FIG. 6, the shifted length isdefined as a first length dt1. Next, when two adjacent output bumps OPBdisposed in the first output bump row OPB_R1 are arranged to overlapeach other in the row direction (that is, a direction in which the firstdirection axis D1 extends) in FIG. 6, the overlapping length is definedas a second length dt2. Next, when an output bump OPB of two adjacentoutput bumps OPB disposed in the first output bump row OPB_R1 isarranged to be shifted to the lower end (that is, in a direction inwhich the second direction axis D2 extends) in FIG. 6, the shiftedlength is defined as a third length dt3. Next, the length between thefirst output bump row OPB_R1 and the second output bump row OPB_R2 isdefined as a fourth length dt4. Here, the fourth length dt4 maycorrespond to a distance between the lower end (that is, a direction inwhich the second direction axis D2 extends) of the output bump OPBdisposed at the lowermost end of the first output bump row OPB_R1 amongthe output bumps OPBs included in the first output bump row OPB_R1 inFIG. 6 and the upper end (that is, a direction opposite to the directionin which the second direction axis D2 extends) of the output bump OPBdisposed at the uppermost end of the second output bump row OPB_R2 amongthe output bumps OPBs included in the second output bump row OPB_R2 inFIG. 6.

In an embodiment, the shapes of the output bumps OPBs included in thefirst through fourth output bump rows OPB_R1, OPB_R2, OPB_R3, and OPB_R4are all the same as each other, and the first length dt1 and the thirdlength dt3 may be equal to each other. Further, the length of one outputbump OPB may be equal to the sum of the first length dt1 and the secondlength dt2, or the sum of the second length dt2 and the third lengthdt3.

As described above, defects due to the conductive balls 510 included inthe anisotropic conductive film 500 can be minimized or reduced byavoiding the excessive zigzag arrangements of the output bumps OPBswhile appropriately adjusting the pressure applied to the firstsubstrate 100 by the output bumps OPBs due to the zigzag arrangement ofthe output bumps OPB. Referring to the following Table 1, FIG. 7 andFIG. 8, some experimental results of experimental examples for obtainingspecific numerical ranges of the arrangements of the output bumps OPBsin a zigzag form, satisfying this condition, are provided.

TABLE 1 Experi- Experi- Experi- Experi- Experi- Experi- Experi- Experi-mental mental mental mental mental mental mental mental Example ExampleExample Example Example Example Example Example 1 2 3 4 5 6 7 8 dt1   0μm   0 μm   9 μm   9 μm   18 μm   18 μm   36 μm   36 μm (=dt3) dt1 + dt2  80 μm   80 μm   80 μm   80 μm   80 μm   80 μm   80 μm   80 μm (=dt2 +dt3) dt4 48.5 μm 43.5 μm 48.5 μm 43.5 μm 48.5 μm 43.5 μm 48.5 μm 43.5 μm

Table 1 above shows the measurement conditions of Experimental Examples1 to 8, which were measured by changing the shifted length between theadjacent output bumps OPBs arranged in the same row (that is, the firstlength dt1 or the third length dt3), the length of one output bump OPBin the column direction (that is, the sum of the first length dt1 andthe second length dt2, or the sum of the second length dt2 and the thirdlength dt3), and the length between the output bump rows OPB_R1, OPB_R2,OPB_R3, and OPB_R4 (that is, the fourth length d4).

FIG. 7 is a graph showing the measured values of pressures applied tothe first to fifth points of FIG. 2 in Experimental Examples 1, 3, 5,and 7. FIG. 8 is a graph showing the measured values of pressuresapplied to the first to fifth points of FIG. 2 in Experimental Examples2, 4, 6, and 8.

In the graphs of FIGS. 7 and 8, the horizontal axis represents thevalues corresponding to the first to fifth points shown in FIG. 2, andthe vertical axis represents the values (unit: MPa) of pressures appliedto the first substrate 100 by the output bumps OPB in the process ofmounting the drive circuit chip 300 on the first substrate 100, wherethe values were measured at the first to fifth points shown in FIG. 2.

Referring to Table 1 and FIGS. 7 and 8, it can be ascertained that, whenthe fourth length dt4 is 43.5 μm, the pressures applied to the first tofifth points decrease as a whole, compared to when the fourth length dt4is 48.5 μm.

Specifically, it can be ascertained that, when the output bump rowsOPB_R1, OPB_R2, OPB_R3, and OPB_R4 are excessively spaced, the pressuresapplied to the first substrate 100 by the output bumps OPBs increases.That is, it can be ascertained that, when the output bump rows OPB_R1,OPB_R2, OPB_R3, and OPB_R4 are spaced within an appropriate numericalrange, the entire region of the first substrate 100, the region beingprovided with the output pads OPDs, may be uniformly or substantiallyuniformly pressed, and thus the pressure applied to the first substrate100 substantially decreases. In contrast, it can be ascertained that,when the output bump rows OPB_R1, OPB_R2, OPB_R3, and OPB_R4 areexcessively spaced, the specific region of the first substrate 100 ofthe region provided with the output pads OPDs is intensively pressed,and, thus, the pressure applied to the first substrate 100 substantiallyincreases.

Further, according to the experimental results shown in Table 1 andFIGS. 7 and 8, it can be ascertained that the pressure applied to thefirst substrate 100 by the output bumps OPBs decreases when the spaceddistance (that is, the fourth length dt4) between adjacent output bumprows OPBRs has a value of 46 μm or less.

Next, referring to Table 1 and FIGS. 7 and 8, it can be ascertained thatthe pressure applied to the first substrate 100 by the output bumps OPBsdecreases as the shifted length (that is, the first length dt1 or thethird length dt3) of the adjacent two output bumps OPBs arranged in thesame output bump row in the column direction (that is, a direction inwhich the second directional axis extends) is increased.

Specifically, it can be ascertained that, in the case of ExperimentalExample 3 or Experimental Example 4 where the first length dt1 or thethird length dt3 has a value of 9 μm, the pressure applied to the firstsubstrate 100 further decreases, compared to the case of ExperimentalExample 1 or Experimental Example 2 where the first length dt1 or thethird length dt3 has a value of 0 μm. Further, it can be ascertainedthat, in the case of Experimental Example 5 or Experimental Example 6where the first length dt1 or the third length dt3 has a value of 18 μm,the pressure applied to the first substrate 100 further decreases,compared to the case of Experimental Example 3 or Experimental Example 4where the first length dt1 or the third length dt3 has a value of 9 μm.Further, it can be ascertained that, in the case of Experimental Example7 or Experimental Example 8 where the first length dt1 or the thirdlength dt3 has a value of 36 μm, the pressure applied to the firstsubstrate 100 further decreases, compared to the case of ExperimentalExample 5 or Experimental Example 6 where the first length dt1 or thethird length dt3 has a value of 18 μm.

However, as described above, the first length dt1 or the third lengthdt3 cannot infinitely increase in order to prevent defects caused by theconductive balls 510 disposed in the anisotropic conductive film 500.Specifically, the shifted length (that is, the first length dt1 or thethird length dt3) of the adjacent two output bumps OPBs included in thesame output bump row OPBR in the column direction (that is, a directionin which the second directional axis extends) may be half or less of thesum of the length of one output bump OPB (that is, the sum of the firstlength dt1 and the second length dt2 or the sum of the second length dt2and the third length dt3) and the spaced length between two consecutiveoutput bump rows OPBR (that is, the fourth length dt4).

That is, dt1 and dt3≤(dt1+dt2+dt4)/2 . . . Equation (1) or dt1 anddt3≤(dt2+dt3+dt4)/2 . . . Equation (2) may be satisfied.

Only when the conditions of the aforementioned Equation (1) or (2) aresatisfied, the anisotropic conductive film 500 can be smoothly deformedin the process of applying heat and pressure to the anisotropicconductive film 500 disposed on the first substrate 100.

Consequently, although the pressure applied to the first substrate 100by the output bumps OPBs decreases when the first length dt1 or thethird length dt3 has a long value, defects due to the conductive balls510 may occur when the first length dt1 or the third length dt3 has anexcessively long value. Therefore, the first length dt1 or the thirdlength dt3 may be determined within a range that satisfies theconditions of Equation (1) or (2).

However, among the aforementioned contents, 46 μm described as thestandard of the length of the fourth length dt4 is a length derivedaccording to the present experimental conditions, and this value mayalso be changed. That is, this value is only a resultant value derivedaccording to the structure of the output bump (OPB) and the output pad(OPD) under the experimental conditions. The specific numerical valuerange of the fourth length dt4 is not limited to the numerical valuedescribed in the present embodiment, and may be changed as necessary,provided that the range of Equation (1) or (2) is satisfied.

Cracks and damage due to the pressure of the aforementioned output bumpsOPBs to the first substrate may more easily occur in the case of aflexible substrate. In this case, the structure according to the presentinvention is further required. Herein, a specific structure of aflexible substrate will be described.

FIG. 9 is a sectional view of a base substrate of the display device ofFIGS. 4 and 5, where the base substrate is a flexible substrate,according to an embodiment of the present invention.

Referring to FIG. 9, in an embodiment, the base substrate 110 has alamination structure of a first plastic film layer 111, a first adhesivelayer 112, a second plastic film layer 113, a second adhesive layer 114,a third plastic film layer 115, and a fourth plastic film layer 116.

The first plastic film layer 111 is made of a polymer material havingexcellent heat resistance, such as polyethylene terephthalate (PET). Thefirst plastic film layer 111, as shown in FIG. 9, can protect thecomponents disposed on the front surface (that is, an upper portion) ofthe first plastic film layer 111 from the impact applied to the backsurface (that is, a lower portion) of the first plastic film layer 111,and may have a strength that is bent to a certain degree. In addition,the first plastic film layer 111 may provide restoring force to relievebending after bending.

The first adhesive layer 112 is disposed on one surface of the firstplastic film layer 111. The first adhesive layer 112 may be made of apressure-sensitive adhesive (PSA). The pressure-sensitive adhesiverefers to an adhesive to which an adhesive material acts when pressureis applied to bond the adhesive to an adhesive surface. No solvent,water, or heat is required to activate the adhesive. As suggested in thename “pressure-sensitive,” the strength of adhesion is influenced by theamount of pressure that causes the adhesive to be applied to a surface.The pressure-sensitive adhesive can usually maintain appropriateadhesiveness and sustainability at room temperature.

The second plastic film layer 113 is disposed on one surface of thefirst adhesive layer 112. The second plastic film layer 113, similarlyto the first plastic film layer 111, is made of a polymer materialhaving excellent heat resistance, such as polyethylene terephthalate(PET). The second plastic film layer 113 may be thicker than the firstplastic film layer 111, and may function to allow the base substrate 110to be bent to an appropriate strength without being excessively bent.

The second adhesive layer 114 is disposed on one surface of the secondplastic film layer 113. The second adhesive layer 114, similarly to thefirst adhesive layer 112, may be made of a pressure-sensitive adhesive(PSA), and may perform the same function as the first adhesive layer112.

The third plastic film layer 115 and the fourth plastic film layer 116are sequentially disposed or stacked on one surface of the secondadhesive layer 114. Each of the third plastic film layer 115 and thefourth plastic film layer 116 is made of a polymer material havingexcellent heat resistance, such as polyimide (PI). The third plasticfilm layer 115 and the fourth plastic film layer 116 may be thinner thanthe first adhesive layer 112 and the second plastic film layer 113.

In an embodiment, due to the lamination structure of the base substrate110, the base substrate 110 can have appropriate bending strength, and adisplay device having flexible characteristics can be manufactured.However, unlike the structure of the base substrate 110 of a generaldisplay device which is not bent, the base substrate 110 according tothe present embodiment includes a plurality of adhesive layers, and thusrelatively larger thickness deformation may be caused when pressure isapplied to the first substrate 100 by the output bumps OPBs of the drivecircuit chip 300. Accordingly, cracks and damage of the output pads OPDand the like may occur relatively easily. However, when the arrangementstructure of the output bumps OPBs according to one or more embodimentsof the present invention is used, cracks or damage of the output padsOPDs and the like can be minimized or reduced, and the drive circuitchip 300 can be stably mounted on the first substrate 100.

FIG. 10 is an enlarged layout diagram of a region corresponding to theregion “B” of FIG. 2 of a display device according to a modifiedembodiment of the present invention; and FIG. 11 is an enlarged layoutdiagram showing output bumps arranged in the region shown in FIG. 10.

The display device according to a modified embodiment of the presentinvention has some differences in the arrangement of output bumps OPB_a,compared with the display device according to the embodiment shown inFIGS. 2 and 6. Therefore, a description of the components denoted by thesame reference numerals will be omitted, and differences will be mainlydescribed.

Referring to FIGS. 10 and 11, the display device according to a modifiedembodiment of the present invention includes first to fourth output bumprows OPB_R1, OPB_R2, OPB_R3, and OPB_R4 in the region corresponding tothe region “B” of FIG. 2. However, the output bumps OPB_a respectivelydisposed in the first to fourth output bump rows OPB_R1, OPB_R2, OPB_R3,and OPB_R4 may be arranged in a zigzag form in a bundle of two outputbumps. That is, in the case of the display device according to anembodiment of the present invention shown in FIGS. 2 and 6, the outputbumps (OPBs of FIG. 6) arranged in the same output bump rows OPB_R1,OPB_R2, OPB_R3 and OPB_R4 are arranged between the most adjacent outputbumps (OPBs of FIG. 6) in a zigzag form, but may differ from thestructure thereof. Further, although not shown, the output bumps OPB_adisposed in the same output bump rows OPB_R1, OPB_R2, OPB_R3, and OPB_R4may also be arranged a zigzag form in a bundle of three or more outputbumps.

In an embodiment, some of the arranged output pads OPDs may be outputpads OPDs used for testing, which function as a path through which atest signal (not shown) is inputted from the outside before attachingthe drive circuit chip (300 of FIG. 1) and which remain not to perform aseparate role after attaching the drive circuit chip (300 of FIG. 1).The output pads OPDs used for testing may be the output pads OPDsdisposed outside. For example, the output pads OPDs disposed in thefirst column of each of the first to fourth output pad rows OPD_R1,OPD_R2, OPD_R3, and OPD_R4 may be output pads OPDs used for testing. Incontrast, the output pads OPDs disposed in the last column of each ofthe first to fourth output pad rows OPD_R1, OPD_R2, OPD_R3, and OPD_R4may be output pads OPDs used for testing.

In addition, when some of the output pads OPD are output pads OPD mainlyused for testing, the pad lines OPLs electrically connected to theseoutput pads OPD may also be pad lines OPLs used for testing.

FIG. 12 is an enlarged layout diagram of a region corresponding to theregion “B” of FIG. 2 of a display device according to another modifiedembodiment of the present invention; and FIG. 13 is an enlarged layoutdiagram showing output bumps arranged in the region shown in FIG. 12.

The display device according to another modified embodiment of thepresent invention has some differences in the arrangement of outputbumps OPB_b, compared with the display device according to theembodiment shown in FIGS. 2 and 6. Therefore, a description of thecomponents denoted by the same reference numerals will be omitted, anddifferences will be mainly described.

Referring to FIGS. 12 and 13, the display device according to anothermodified embodiment of the present invention includes first to fourthoutput bump rows OPB_R1, OPB_R2, OPB_R3, and OPB_R4 in the regioncorresponding to the region “B” of FIG. 2.

The upper ends of the output bumps OPB_b disposed in each of the firstto fourth output bump rows OPB_R1, OPB_R2, OPB_R3, and OPB_R4 (here, theupper end refers to the end disposed in the upward direction of FIGS. 12and 13, that is, the end disposed in the direction opposite thedirection in which the second directional axis D2 extends) may bearranged in a zigzag form, whereas the lower ends of the output bumpsOPB_b (here, the lower end refers to the end disposed in the downwarddirection of FIGS. 12 and 13, that is, the end disposed in the directionin which the second directional axis D2 extends) may be arranged inparallel.

Due to such a structure, a degree to which the output bumps OPB_b arearranged in a zigzag form is relatively relieved compared with theoutput bumps (OPBs of FIGS. 2 and 6) of the display device according tothe embodiment shown in FIGS. 2 and 6, so as to minimize or reduce theoccurrence of defects due to the anisotropic conductive film 500.

FIG. 14 is an enlarged layout diagram of a region corresponding to theregion “B” of FIG. 2 of a display device according to another modifiedembodiment of the present invention; and FIG. 15 is an enlarged layoutdiagram showing output bumps arranged in the region shown in FIG. 14.

The display device according to another modified embodiment of thepresent invention has some differences in the structure of output bumpsOPB_c, compared with the display device according to the embodimentshown in FIGS. 2 and 6. Therefore, a description of the componentsdenoted by the same reference numerals will be omitted, and differenceswill be mainly described.

Referring to FIGS. 14 and 15, the display device according to anothermodified embodiment of the present invention includes first to fourthoutput bump rows OPB_R1, OPB_R2, OPB_R3, and OPB_R4 in the regioncorresponding to the region “B” of FIG. 2.

The output bumps OPB_c arranged in each of the first to fourth outputbump rows OPB_R1, OPB_R2, OPB_R3, and OPB_R4 may have different shapesbetween adjacent output bumps OPB_c. In an embodiment, among therespective output bumps OPB_c arranged in the first output bump rowOPB_R1, a length (that is, a sum of a first length dt1, a second lengthdt2 and a third length dt3) in the column direction (that is, adirection in which the second directional axis D2 extends) ofeven-numbered output bumps OPB may be longer than a length (that is, thesecond length dt2) extending in the column direction (that is, adirection in which the second directional axis D2 extends) ofodd-numbered output bumps OPB_c. In an embodiment (not shown), incontrast to the first output bump row OPB_R1, among the respectiveoutput bumps OPB_c arranged in the second output bump row OPB_R2, thelength in the column direction (that is, a direction in which the seconddirectional axis D2 extends) of the even-numbered output bumps OPB maybe shorter than the length extending in the column direction (that is, adirection in which the second directional axis D2 extends) of theodd-numbered output bumps OPB_c. The third output bump row OPB_R3 andthe fourth output bump row OPB_R4 may have the same arrangement as thefirst output bump row OPB_R1 and the second output bump row OPB_R2,respectively.

Due to this structure, even if the shapes of the output bumps OPB_cadjacent to each other are different, a zigzag arrangement structure canbe maintained.

FIG. 16 is an enlarged layout diagram of a region corresponding to theregion “B” of FIG. 2 of a display device according to another modifiedembodiment of the present invention.

The display device according to another modified embodiment of thepresent invention is different from the display device according to theembodiment shown in FIG. 2 in that the shapes of some output pads OPD_nare different from the shapes of other output pads OPD_m. Therefore, adescription of the components denoted by the same reference numeralswill be omitted, and differences will be mainly described.

Referring to FIG. 16, the display device according to another modifiedembodiment of the present invention includes first to fourth output padrows OPD_R1, OPD_R2, OPD_R3, and OPD_R4 in the region corresponding tothe region “B”. Further, drive output pads OPD_m or inspection outputpads OPD_n are arranged in each of the first to fourth output pad rowsOPD_R1, OPD_R2, OPD_R3, and OPD_R4.

The drive output pads OPD_m perform a function of transmitting a drivesignal. The respective drive output pads OPD_m arranged in the same rowmay be formed to have the same shape, and may be arranged parallel toeach other. The drive output pads OPD_m disposed in the display deviceaccording to an embodiment of the present invention may have the sameshape as the output pads (OPD of FIGS. 2 and 6) disposed in the displaydevice according to the embodiment shown in FIG. 2, and may perform thesame function as the output pads (OPD of FIGS. 2 and 6).

The inspection output pads OPD_n serve to check whether the drivecircuit chip 300 is normally mounted on the first substrate 100 withoutmisalignment. The inspection output pads OPD_n may be arranged in a verysmall number between the plurality of drive output pads OPD_m, and mayhave a relatively small size compared with the drive output pads OPD_m.

In an embodiment, a width of the inspection output pad OPD_n in the rowdirection (that is, a direction in which the first directional axis D1extends) may be equal to a width of the drive output pad OPD_m in therow direction (that is, a direction in which the first directional axisD1 extends). In contrast, a length of the inspection output pad OPD_n inthe column direction (that is, a direction in which the seconddirectional axis D2 extends) may be shorter the length of the driveoutput pad OPD_m in the column direction (that is, a direction in whichthe second directional axis D2 extends). In an embodiment, theinspection output pad OPD_n may be formed in a similar shape to theoutput bump OPB disposed corresponding thereto, and may be disposed atthe same position.

In an embodiment, as shown in FIG. 16, the inspection output pad OPD_nmay extend to a shorter length than the output pad OPD_m disposedcorresponding thereto. That is, the length of the inspection output padOPD_n extending in the column direction (that is, a direction in whichthe second directional axis D2 extends) may be shorter than the lengthof the output pad OPD_m extending in the column direction (that is, adirection in which the second directional axis D2 extends).

A method for checking whether the drive circuit chip 300 is misalignedusing the inspection output pads OPD_n according to an embodiment willbe described. First, the drive circuit chip 300 is mounted, and then thedrive circuit chip 300 provides a test signal to the inspection outputpads OPD_n. Then, the voltage of the test signal is measured from theinspection output pads OPD_n arranged on the first substrate 100. Ifmisalignment of the drive circuit chip 300 does not occur, the voltageof the test signal detected from the first substrate 100 may be close toa preset reference value, but, if misalignment of the drive circuit chip300 occurs, the voltage of the test signal detected from the firstsubstrate 100 may not reach the preset reference value. The reason forthis is that if the misalignment of the drive circuit chip 300 occurs,the overlapping area of the inspection output pad OPD_n and the outputbump OPB may become small because the inspection output pad OPD_n andthe output bump OPB disposed corresponding thereto are formed in thesame shape and arranged at the same position.

FIGS. 17 to 21 are enlarged layout diagrams respectively showing outputbumps of display devices arranged in regions corresponding to the region“B” of FIG. 2, according to other modified embodiments of the presentinvention.

Each of the display devices according to the other modified embodimentsof the present invention is different from the display device accordingto the embodiment shown in FIG. 2 in the shape of output bumps OPB_e,OPB_f, OPB_g, OPB_h, and OPB_i. Therefore, a description of thecomponents denoted by the same reference numerals will be omitted, anddifferences will be mainly described.

Referring to FIG. 17, a display device according to another modifiedembodiment of the present invention includes output bumps OPB_e having aparallelogram shape. Further, referring to FIG. 18, a display deviceaccording to another modified embodiment of the present inventionincludes output bumps OPB_f having a rectangular shape with ends whereadjacent sides meet each other being cut off, or chamfered. Further,referring to FIG. 19, a display device according to another modifiedembodiment of the present invention includes output bumps OPB_g havingan elliptical shape. Further, referring to FIG. 20, a display deviceaccording to another modified embodiment of the present inventionincludes output bumps OPB_h having a diamond shape with upper and lowerends are cut off. Further, referring to FIG. 21, a display deviceaccording to another modified embodiment of the present inventionincludes output bumps OPB_i having a diamond shape.

In one or more embodiments, if the respective output pads arranged onthe first substrate 100 satisfy the conditions having the same shape aseach other, the shape of the output bumps OPB can be variously designed.Accordingly, when heat and pressure are applied to the anisotropicconductive film 500 in the process of connecting the drive circuit chip300, the flow of the conductive balls 510 not in contact with the outputbumps OPB or the output pads OPD may be changed depending on the shapeof the output bumps OPB, and design freedom may be increased inconsideration of this phenomenon.

FIG. 22 is a layout view showing bumps and pads of a display devicearranged in a region corresponding to the region “A” of FIG. 1,according to another modified embodiment of the present invention.

The display device according to another modified embodiment of thepresent invention is different from the display device according to theembodiment shown in FIG. 2 in that the number of rows formed by theoutput pads OPD is relatively decreased. Therefore, a description of thecomponents denoted by the same reference numerals will be omitted, anddifferences will be mainly described.

Referring to FIG. 22, the first substrate 100 of the display deviceaccording to another modified embodiment of the present inventionincludes an input pad region IPDR, a side pad region SPDR, and an outputpad region OPDR_j.

A plurality of input pads IPD may be arranged in the input pad regionIPDR, and a plurality of side pads SPD may be arranged in the side padregion SPDR. Since, in an embodiment, the input pad region IPDR and theside pad region SPDR may be the same as those having been described withreference to FIG. 2, the description thereof will be omitted.

A plurality of output pads OPD are arranged in the output pad regionOPDR_j, and may be arranged to form a total of three rows. That is, likethe display device according to the embodiment shown in FIG. 2, theoutput pad region (OPDR of FIG. 2) is not limited to the arrangement ofoutput pads OPD of four rows, and may also be provided with output padsOPD of three rows. Further, although not shown in the drawings, thenumber of rows of the output pads OPD disposed in the output pad regionOPDR_j is not limited to four or three, and may also be two or less orfive or more.

FIG. 23 is a layout view showing bumps and pads of a display devicearranged in a region corresponding to the region “A” of FIG. 1,according to another modified embodiment of the present invention.

The display device according to another modified embodiment of thepresent invention is different from the display device according to theembodiment shown in FIG. 2 in that output pads OPD_k and output bumpsOPB_k are formed so as to face in different directions. Therefore, adescription of the components denoted by the same reference numeralswill be omitted, and differences will be mainly described.

Referring to FIG. 23, the first substrate 100 of the display deviceaccording to another modified embodiment of the present inventionincludes an input pad region IPDR, a side pad region SPDR, and an outputpad region OPDR.

A plurality of input pads IPD may be arranged in the input pad regionIPDR, and a plurality of side pads SPD may be arranged in the side padregion SPDR. Since, in an embodiment, the input pad region IPDR and theside pad region SPDR may be the same as those having been described withreference to FIG. 2, the description thereof will be omitted.

A plurality of output pads OPD_k are arranged in the output pad regionOPDR, and may be arranged to form a plurality of rows. In an embodiment,the plurality of output pads OPD_k may be arranged to form first tofourth output pad rows OPD_R1, OPD_R2, OPD_R3, and OPD_R4.

Further, the output pads OPD_k arranged in the same row may be arrangedin parallel along the row direction (that is, a direction in which thefirst direction axis D1 extends). Some of the respective output padsOPD_k extend along the column direction (that is, a direction in whichthe second directional axis D2 extends), and the others of the outputpads OPD_k extend in the column direction (that is, a direction in whichthe second directional axis D2 extends) to have a predeterminedinclination.

Further, each of the output bumps OPB_k arranged to correspond to theoutput pads OPD_k may also have a similar structure to the output pad.That is, the output bumps OPB_k arranged in the same row may be arrangedin parallel along the row direction (that is, a direction in which thefirst direction axis D1 extends). Some of the respective output bumpsOPB_k extend along the column direction (that is, a direction in whichthe second directional axis D2 extends), and the others thereof extendin the column direction (that is, a direction in which the seconddirectional axis D2 extends) to have a predetermined inclination.

In an embodiment, among the output pads OPD_k arranged in the firstoutput pad row OPD_R1, the output pads OPD_k disposed at the centershown in FIG. 23 extend in the column direction (that is, a direction inwhich the second directional axis D2 extends). Among the output padsOPD_k arranged in the first output pad row OPD_R1, remaining output padsOPD_k, except for the output pads OPD_k disposed at the center, mayextend in a direction in which an inclination gradually increasescompared with the column direction (that is, a direction in which thesecond directional axis D2 extends) as these remaining output pads OPD_kare farther away from the output pads OPD_k disposed at the center. Thisarrangement of the output pads OPD_k in the first output pad row OPD_R1may be equally applied to the output pads OPD_k of the second to fourthoutput pad rows OPD_R2, OPD_R3, and OPD_R4. Further, among the outputpads OPD_k disposed in each of the first to fourth output pad rowsOPD_R1, OPD_R2, OPD_R3, and OPD_R4, the output pads OPD_k disposed atthe center of each of the first to fourth output pad rows OPD_R1,OPD_R2, OPD_R3, and OPD_R4 are not limited in extending in the columndirection (that is, a direction in which the second direction axis D2extends), and the other output pads OPD_k may extend in the columndirection (that is, a direction in which the second direction axis D2extends). Further, all of the output pads OPD_k may also be formed tohave a predetermined inclination with respect to the column direction(that is, a direction in which the second directional axis D2 extends).

In addition, each of the output bumps OPB_k may be formed to be inclinedso as to coincide with the inclination of the corresponding output padOPD_k.

Through the structure of the output pads OPD_k and the output bumpsOPB_k, when the drive circuit chip 300 is misaligned in the columndirection (that is, a direction in which the second directional axis D2extends), this misalignment can be easily corrected.

However, even if the output pad OPD_k and the output bump OPB_kaccording to the present embodiment are arranged in the same row, theextended lengths may be different from each other. That is, some of theoutput pads OPD_k and output bumps OPB_k extend along the columndirection (that is a direction in which the second directional axis D2extends), whereas the others thereof extend along a direction inclinedto the column direction. Therefore, the lengths of the respective outputpads OPD_k and output bumps OPB_k, which are measured along the extendeddirection, may be different.

Illustratively, since the output pads OPD_k disposed at the center ofthe first output pad row OPD_R1 extend in the column direction (that is,a direction in which the second directional axis D2 extends), the lengthmeasured in the extending direction may be equal to the length measuredin the column direction (that is, a direction in which the seconddirectional axis D2 extends). In contrast, in the case of the outputpads OPD_k not disposed at the center of the first output pad rowOPD_R1, the length measured in the extending direction may be longerthan the length measured in the column direction (that is, a directionin which the second directional axis D2 extends). In particular, as theoutput pads OPD_k are arranged to be away from the center of the firstoutput pad row OPD_R1, the extending length may become longer. Althoughthe structure of the output pads OPD and the output bumps OPB has beendescribed throughout this specification, this structure may be equallyapplied to the input pads IPD and the input bumps IPB. Moreover, thisstructure may also be equally applied to the side pads SPD and the sidebumps SPB.

As described above, according to embodiments of the present invention, adisplay device includes a drive circuit chip safely mounted on asubstrate without causing cracks or damage.

The effects of the present invention are not limited by the foregoing,and other various effects are anticipated herein.

Although some exemplary embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas set forth in the accompanying claims.

The effects of the present invention are not limited by the foregoing,and other various effects are anticipated herein.

Further, those skilled in the art will appreciate that many variationsand modifications can be made to the described exemplary embodimentswithout substantially departing from the principles of the presentinvention. Therefore, the disclosed exemplary embodiments of theinvention are used in a generic and descriptive sense only and not forpurposes of limitation.

What is claimed is:
 1. A display device comprising: a substrate;conductive pads arranged on the substrate, the conductive pads includinga first conductive pad, a second conductive pad, a third conductive pad,a fourth conductive pad, a fifth conductive pad, and a sixth conductivepad; and a drive circuit chip including bumps electrically connectedwith the conductive pads, the bumps including a first bump overlappingthe first conductive pad, a second bump overlapping the secondconductive pad, a third bump overlapping the third conductive pad, afourth bump overlapping the fourth conductive pad, a fifth bumpoverlapping the fifth conductive pad, and a sixth bump overlapping thesixth conductive pad, wherein the first conductive pad, the secondconductive pad, the third conductive pad, the fourth conductive pad, thefifth conductive pad, and the sixth conductive pad are arranged in afirst direction and each overlap a reference line extending in the firstdirection, wherein the second conductive pad, the third conductive pad,the fourth conductive pad, and the fifth conductive pad are extended ina second direction intersecting the first direction, wherein the firstconductive pad is extended in a third direction which is different fromthe first direction and the second direction, wherein the sixthconductive pad is extended in a fourth direction which is different fromthe first direction, the second direction, and the third direction,wherein each of the second bump, the third bump, the fourth bump, andthe fifth bump includes a first end and a second end opposite to thefirst end in the second direction, and wherein the first end of one ofthe second bump, the third bump, the fourth bump, and the fifth bump isshifted in the second direction relative to the first end of another oneof the second bump, the third bump, the fourth bump, and the fifth bump.2. The display device of claim 1, wherein the second bump, the thirdbump, the fourth bump, and the fifth bump are sequentially disposed inthe first direction.
 3. The display device of claim 2, wherein the firstend of the third bump is shifted in the second direction relative to thefirst end of the second bump, and wherein the first end of the fifthbump is shifted in the second direction relative to the first end of thefourth bump.
 4. The display device of claim 3, wherein a shifted lengthbetween the first end of the third bump and the first end of the secondbump is substantially the same as a shifted length between the first endof the fifth bump and the first end of the fourth bump.
 5. The displaydevice of claim 3, wherein the second end of the third bump is shiftedin the second direction relative to the second end of the second bump,and wherein the second end of the fifth bump is shifted in the seconddirection relative to the second end of the fourth bump.
 6. The displaydevice of claim 5, wherein a shifted length between the first end of thethird bump and the first end of the second bump is substantially thesame as a shifted length between the first end of the fifth bump and thefirst end of the fourth bump, and wherein a shifted length between thesecond end of the third bump and the second end of the second bump issubstantially the same as a shifted length between the second end of thefifth bump and the second end of the fourth bump.
 7. The display deviceof claim 6, wherein the shifted length between the first end of thethird bump and the first end of the second bump is substantially thesame as the shifted length between the second end of the third bump andthe second end of the second bump.
 8. The display device of claim 3,wherein a length of the third bump is longer than a length of the secondbump, and wherein a length of the fifth bump is longer than a length ofthe fourth bump.
 9. The display device of claim 8, wherein the secondend of the second bump, the second end of the third bump, the second endof the fourth bump, and the second end of the fifth bump are aligned inthe first direction.
 10. The display device of claim 8, wherein thesecond end of the third bump and the second end of the fifth bump arealigned in the first direction, wherein the second end of the secondbump and the second end of the fourth bump are aligned in the firstdirection, and wherein the second end of the second bump and the secondend of the third bump are not aligned in the first direction.
 11. Thedisplay device of claim 2, wherein the first end of the fourth bump andthe first end of the fifth bump are shifted in the second directionrelative to the first end of the third bump.
 12. The display device ofclaim 11, wherein the first end of the fourth bump and the first end ofthe fifth bump are aligned in the first direction, and wherein the firstend of the second bump and the first end of the third bump are alignedin the first direction.
 13. The display device of claim 11, wherein thesecond end of the fourth bump and the second end of the fifth bump areshifted in the second direction relative to the second end of the thirdbump, and wherein the second end of the second bump and the second endof the third bump are aligned in the first direction.